The Husqvarna 550XP

[1990Husky262]

Exhaust--578 041 801
Carb--574 711 402
Strato Ports-- 578 021 301 (2 required)

Thanks

 

[nwhunter]

I am new to these auto tune saws.
I bought an ebay 550xp saw that looked clean with bad piston and cylinder, as well as broken choke shaft. 2012 build date.
I installed an oem piston and cylinder as well as a new choke shaft bearings looked and felt good and saw passed pressure and vacuum tests.
Next I opened up the muffler to try to lesson retained heat.
Spent yesterday afternoon running it and I was impressed.
Saw is a screamer, with the 18" bar I put on it.
It felt like it had as much or more power than my 55 or 359, plus it is light and nimble.
Immediately after running it I checked temps with a laser gun.
I showed 80 degrees on the carb, 180 on transfer covers, 170 on rest of cylinder, 210 on muffler at port area, 150 at exhaust from muffler.
Would any of these be of concern?
I did open up the top cover to resemble the newer covers for the 550 and 562 series when I was working on the saw.

 

[Loony661]

Need some help:
Buddy dropped off his 550XP to me to look at. Said it won’t run.. I can get it to “pop” on first pull with choke. Shut choke off and it won’t even try to start.. Muffler is now wet. Hold throttle open and pull a dozen times and it’ll “chug” for a few pull then finally take off - and it takes a few seconds to clear the extra fuel of course, but after that it screams and runs smooth on the throttle. As soon as I let the throttle down to idle the saw, it floods and dies. Usually hard enough that I cannot restart it for a while, even with the throttle open.. I’m new to these AutoTune saws - am I able to repair this at home? Or does this need to go to a Husqvarna dealer (we don’t have any locally)?? Any info appreciated..

 

[Loony661]

I should add that I already had the carb apart and all was good. Used to carb spray and light compressed air and cleaned all the circuits. I would like to put a kit in it if that will fix it, but I’m not going to waste time/money until I know what I’m up against..

 

[Stump Shot]

Need some help:
Buddy dropped off his 550XP to me to look at. Said it won’t run.. I can get it to “pop” on first pull with choke. Shut choke off and it won’t even try to start.. Muffler is now wet. Hold throttle open and pull a dozen times and it’ll “chug” for a few pull then finally take off - and it takes a few seconds to clear the extra fuel of course, but after that it screams and runs smooth on the throttle. As soon as I let the throttle down to idle the saw, it floods and dies. Usually hard enough that I cannot restart it for a while, even with the throttle open.. I’m new to these AutoTune saws - am I able to repair this at home? Or does this need to go to a Husqvarna dealer (we don’t have any locally)?? Any info appreciated..

I just went through this with a lightly used 660, the throttle plate was slammed shut tight to the bore not letting any air in, plus the multi lever was broken, not kicking the throttle up when choked. You would have to take off the carb adapter to confirm/deny this to look down the bore and see.

 

[Int1968]

When they first came out we had problems with them not wanting to start when hot or warm, always had to put the choke on then push lever up to fast idle then they’d start fine. Idk might have been gen 1 of the auto tune, drove me nuts.